Logan-area historical earthquake activity is slightly above North Dakota state average. It is 65% smaller than the overall U.S. average. On 8/18/1959 at 06:37:13, a magnitude 7.7 (7.7 UK, Class: Major, Intensity: VIII - XII) earthquake occurred 516.3 miles away from the city center, causing $26,000,000 total damage.
1 Pluto was reclassified from a planet to a dwarf planet in 2006.  Pluto was discovered on February 18th, 1930 by the Lowell Observatory. For the 76 years between Pluto being discovered and the time it was reclassified as a dwarf planet it completed under a third of its orbit around the Sun.
Pluto was demoted to dwarf planet status in 2006, joining Eris, Haumea, Makemake and Ceres. Learn more about the dwarf planets of the solar system in this SPACE.com infographic.